The cannabis plant include constituents such as cannabinoids having numerous therapeutically beneficial applications that have been used to treat a variety of diseases and conditions for centuries. For example, cannabinoids may be used to treat glaucoma, arthritis, insufficient appetite associated with anorexia or HIV/AIDS, posttraumatic stress disorder, insomnia, nausea arising from chemotherapy, and chronic pain, among others.
Among the medically significant cannabinoids found in the cannabis plant are tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabidivarin (CBDV). In particular, THC has anti-inflammatory, analgesic, neuroprotective, and anticonvulsant properties. CBD has been found to have analgesic, anti-inflammatory, antispasmodic, and antipsychotic properties. Both CBD and CBDV are reported to have anticonvulsant properties useful in treatment of various forms of epilepsy, especially in children.
These cannabinoids, along with others, as well as terpenes and flavonoids may be extracted from the cannabis plant to harness their medicinal properties. The extracted oil may be further refined to isolate particular cannabinoids or blends of cannabinoids for desired uses.
Extracting cannabis oil from cannabis plants generally employs a solvent or non-solvent based extraction technique. Non-solvent based techniques include rosin and dry sifting. Water-based techniques are also considered to be non-solvent based techniques. Solvent-based techniques for extracting cannabis oil include supercritical CO2 and hydrocarbon extraction.
Supercritical CO2 extraction utilizes high pressures and extremely low temperatures to extract cannabis oil using carbon dioxide in liquid form. While the CO2 may ultimately be removed from the final product, equipment cost is notably high and lacks scalability. Supercritical CO2 extraction is currently the preferred standard technique utilized by the industry.
Hydrocarbon extraction typically requires washing milled plant material with a liquid hydrocarbon solvent such as butane or propane. An alcohol may also be used. The mixture is then filtered and the filtrate is heated under vacuum to remove the solvent to produce butane hash oil. Winterization using an ethanol solvent may be used to clean the product and produce shatter.